Serena leads Venus (pictured) 15-11 in the head-to-head battle, although Venus will no doubt draw on her win in last year's Canadian Masters.

"She's beaten me so many times," Serena said. "So yeah, she's a player that knows how to win, knows how to beat me, knows my weaknesses better than anyone. She's doing well, and she wants to win this. So do I. It's not going to be easy."

In the men's quarters, top seed Novak Djokovic will take on Spain's Feliciano Lopez, while defending champ Marin Cilic will meet Jo-Wilfried Tsonga.